* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen',
    'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue',
    sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  background-color: #f5f7fa;
}

.app {
  min-height: 100vh;
  width: 100%;
  display: flex;
  flex-direction: column;
}

html, body, #root {
  margin: 0;
  padding: 0;
  height: 100%;
}

#root {
  display: flex;
  flex-direction: column;
  max-width: 100%;
  margin: 0 auto;
  padding: 0;
}

.logo {
  height: 6em;
  padding: 1.5em;
  will-change: filter;
  transition: filter 300ms;
}
.logo:hover {
  filter: drop-shadow(0 0 2em #646cffaa);
}
.logo.react:hover {
  filter: drop-shadow(0 0 2em #61dafbaa);
}

@keyframes logo-spin {
  from {
    transform: rotate(0deg);
  }
  to {
    transform: rotate(360deg);
  }
}

@media (prefers-reduced-motion: no-preference) {
  a:nth-of-type(2) .logo {
    animation: logo-spin infinite 20s linear;
  }
}

.card {
  padding: 2em;
}

.read-the-docs {
  color: #888;
}

.main-content {
  margin-top: 70px; /* 为固定定位的导航栏留出空间 */
  padding: 2rem;
  max-width: 1200px;
  margin-left: auto;
  margin-right: auto;
  width: 100%;
  flex: 1;
}
